Use of a rotating wire cage for retention of animal cells in a perfusion fermentor.

Separation of cells within a perfused suspension system is still a problem. We modified the rotating steel wire cage described by other researchers (2) for separation of single cells from suspension. The system was mounted to the stirrer shaft of a circular-loop fermenter. After optimization of fermenter design experimental data showed good separation of cells at useful perfusion rates. Data of a 5 l-prototype show with a mammalian tumor cell line a retention rate of better than 95% at a perfusion rate of D = 0.05. Scaling-up studies show a good scaling-up potential and a wide range of possible applications.